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Open-shell

The H + NO2 OH + NO reaetion provides an exeellent example of the use of laser fluoreseenee deteetion for the elueidation of the dynamies of a ehemieal reaetion. This reaetion is a prototype example of a radieal-radieal reaetion in that the reagents and produets are all open-shell free radieal speeies. Both the hydroxyl and nitrie oxide produets ean be eonveniently deteeted by eleetronie exeitation in the UV at wavelengths near 226 and 308 mn, respeetively. Atlases of rotational line positions for the lowest eleetronie band systems of these... [Pg.2074]

Figure B2.3.14. Experimentally derived vibration-rotation populations for the NO produet from the H + NO2 reaetion [43], The fme-stnieture labels and refer to the two ways that the projeetions 2 and A of the eleetron spin and orbital angular momenta along the intemuelear axis of this open-shell ean be eoupled (D =... Figure B2.3.14. Experimentally derived vibration-rotation populations for the NO produet from the H + NO2 reaetion [43], The fme-stnieture labels and refer to the two ways that the projeetions 2 and A of the eleetron spin and orbital angular momenta along the intemuelear axis of this open-shell ean be eoupled (D =...
In most tiieoretical treatments of the collision dynamics, the reaction is assumed to proceed on a single PES. However, reactions involving open-shell reagents of products will involve several PESs. For example, in the F + H2 reaction, discussed in section B2.3.2.4. tluee PESs emanate from the separated reagents, of which only... [Pg.2085]

As fonnulated above, the FIF equations yield orbitals that do not guarantee that F has proper spin symmetry. To illustrate, consider an open-shell system such as the lithium atom. If Isa, IsP, and 2sa spin orbitals are chosen to appear in F, the Fock operator will be... [Pg.2168]

The olassio papers in whioh the SCF equations for olosed- and open-shell systems are treated are ... [Pg.2194]

Roothaan C C J 1960 Self-oonsistent field theory for open shells of eleotronio systems Rev. Mod. Phys. 32 179-85... [Pg.2194]

Bobrowiez F W and Goddard W A III 1977 The self-eonsistent field equations for generalized valenee bond and open-shell Hartree-Foek wave funetions Modern Theoretical Chemistry vo 3, ed H F III Sehaefer (New York Plenum) pp 97-127... [Pg.2196]

VIsser O, Vlssoher L, Aerts P J C and NIeuwpoort W C 1992 Moleoular open shell oonflguratlon Interaotlon oaloulatlons using the Dlrao-Coulomb Flamlltonlan the f -manlfold of an embedded cluster J. Chem. Phys. 96 2910-19... [Pg.2234]

Hamilton T P and Pulay P 1986 Direct Inversion In the Iterative subspace (DNS) optimization of open-shell, excited-state and small multiconfiguratlonal SCF wavefunctlons J. Chem. Phys. 84 5728... [Pg.2357]

The spherical shell model can only account for tire major shell closings. For open shell clusters, ellipsoidal distortions occur [47], leading to subshell closings which account for the fine stmctures in figure C1.1.2(a ). The electron shell model is one of tire most successful models emerging from cluster physics. The electron shell effects are observed in many physical properties of tire simple metal clusters, including tlieir ionization potentials, electron affinities, polarizabilities and collective excitations [34]. [Pg.2393]

Llacay J, Veciana J, Vidal-Gancedo J, Bourdelande J L, Gonzalez-Moreno R and Rovira C 1998 Persistent and transient open-shell species derived from Cgg-TTF cyclohexane-fused dyads J. Org. Chem. 63 5201-10... [Pg.2435]

WFth all semi-empirical methods, IlyperChem can also perform psendo-RIfF calculations for open -shell systems. For a doublet stale, all electrons except one are paired. The electron is formally divided into isvo "half electron s" with paired spins. Each halfelec-... [Pg.46]

Although LHF is often a better theoretical treatment of open-shell systems than the RHF (half-electron) methods, it takes longer to compute. Separate matrices for electrons of each spin roughly double the length of the calculation. ... [Pg.47]

Some systems converge poorly, particularly those with multiple bonds or weak interactions between open-shell systems. HyperChem includes two convergence accelerators. One is the default con verge rice accelerator, effective in speed in g up ri orm ally... [Pg.47]

Total spin den sity reflects th e excess probability of fin din g a versus P electrons in an open-shell system. Tor a system m which the a electron density is equal to the P electron density (for example, a closed-shell system), the spin density is zero. [Pg.52]

Choose LHH(spin Unrestricted Hartree-Fock) or RHF (spin Restricted Ilartree-Fock) calculations according to your molecular system. HyperChem supports UHF for both open-sh el I and closed-shell calcii lation s an d RHF for cUised-shell calculation s on ly, Th e closed-shell LHFcalculation may be useful for studyin g dissociation of m olectilar system s. ROHF(spin Restricted Open-shell Hartree-Fock) is not supported in the current version of HyperChem (for ah initio calculations). [Pg.112]

On e would ii ormally choose RHF for closed-sh ell sin gleis an d I. IIF for open-shell doublets and triplets. [Pg.112]

IXDCf is faster than MINDO/3, MNDO, AMI, and PM3 and, unlike C XDO, can deal with spin effects. It is a particularly appealing choice for UHF calculations on open-shell molecules. It is also available for mixed mode calculations (see the previous section ). IXDO shares the speed and storage advantages of C XDO and is also more accurate. Although it is preferred for numerical results, it loses some of the simplicity and inierpretability of C XDO. [Pg.149]

Drowicz F W and W A Goddard IB 1977. The Self-Consistent Field Equations for Generalized Valence Bond and Open-Shell Hartree-Fock Wave Functions. In Schaeffer H F III (Editor). Modem Theoretical Chemistry III, New York, Plenum, pp. 79-127. [Pg.180]

As illustrated above, the spatial symmetries of these four S = 1 and S = 0 states are obtained by forming the direet produet of the "open-shell" orbitals that appear in this eonfiguration b2 x bi = A2. [Pg.266]

The teehniques used earlier for linear moleeules extend easily to non-linear moleeules. One begins with those states that ean be straightforwardly identified as unique entries within the box diagram. For polyatomie moleeules with no degenerate representations, the spatial symmetry of eaeh box entry is identieal and is given as the direet produet of the open-shell orbitals. For the formaldehyde example eonsidered earlier, the spatial symmetries of the nji and nn states were A2 and Ai, respeetively. [Pg.266]


See other pages where Open-shell is mentioned: [Pg.287]    [Pg.874]    [Pg.2075]    [Pg.2168]    [Pg.2340]    [Pg.2341]    [Pg.2447]    [Pg.2451]    [Pg.310]    [Pg.38]    [Pg.45]    [Pg.228]    [Pg.233]    [Pg.243]    [Pg.330]    [Pg.128]    [Pg.128]    [Pg.129]    [Pg.248]    [Pg.265]    [Pg.265]    [Pg.267]   
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A Computer-Algebraic Approach to the Derivation of Feynman-Goldstone Perturbation Expansions for Open-Shell Atoms and Molecules

A WEB for spin-restricted open shell

Asymmetric open shell

Atomic orbitals open-shell configuration

Atoms in open-shell molecules

Barrier means a cost of opening the closed-shells

Bonding in Open-Shell Transition-Metal Complexes

Cluster Theory for Open-Shell Molecules

Clusters open-shell

Configuration general open-shell

Configuration interaction , open-shell

Configuration interaction , open-shell effect

Coupled-cluster approximation, open-shell

Coupled-cluster approximation, open-shell molecules

Coupled-cluster theory open-shell

Coupled-cluster theory open-shell systems

Defects open-shell

Density functional theory , open-shell

Density open-shell character

Doublet open-shell ground states

Electron open shell

Electron propagator theory , open-shell

Electronic Spectroscopy of High Temperature Open-Shell Polyatomic Molecules

Electrostatic interactions open-shell electrons

Energy expression open-shell system

Features in Electronic Spectra of Open-Shell Systems

Fock matrix high-spin open-shell

Fock matrix open-shell systems

For open-shell system

Force constants, open-shell molecules

Functional Theory for Open-Shell Molecules

Hartree open-shell species

Hartree restricted open-shell

Hartree-Fock theory restricted open-shell

Helium, confined open-shell

High-spin open-shell

High-spin open-shell coupled-cluster theory

Kramers-Restricted Open-Shell Methods

Lewis structure open-shell

Local-density approximation open-shell

Many-body perturbation theory open-shell

Many-body perturbation theory open-shell molecules

Matrix diagonalization, open-shell molecules

Metallocenes open shell

Molecular beam electric resonance of open shell molecules

Molecular orbitals, open-shell molecules

Open Shell Atomic Beam Scattering and the Spin Orbit Dependence of Potential Energy Surfaces

Open d shells

Open shell atom photoionization

Open shell atoms

Open shell reactions

Open shell species, potential energy

Open shell species, potential energy surfaces

Open shell states with both spin and orbital angular momentum

Open shell systems curve

Open shell systems triplet

Open shell transition local spin

Open shells implementing UHF

Open- shell states

Open-Shell Benzenoid Polycyclic Hydrocarbons

Open-Shell Electronic Structures

Open-Shell Kramers-Restricted Coupled-Cluster Expansions

Open-shell CISD calculations

Open-shell Hartree-Fock theory (RHF)

Open-shell Lewis structures and spin hybrids

Open-shell NBOs

Open-shell Pseudohamiltonians

Open-shell biradicals

Open-shell calculation

Open-shell cases

Open-shell cluster expansion approach

Open-shell computational methods

Open-shell computations

Open-shell configuration

Open-shell electronic states

Open-shell exchange matrix

Open-shell implementation

Open-shell ion

Open-shell many body formalism

Open-shell methods

Open-shell molecular orbitals calculations

Open-shell molecules

Open-shell organic molecules

Open-shell perturbation theory

Open-shell porphyrin

Open-shell singlet

Open-shell singlet state

Open-shell species

Open-shell species DODS)

Open-shell species spins

Open-shell systems

Open-shell systems clusters

Open-shell systems, electron correlation

Open-shell systems, photoionization

Open-shell transition metal ions

Open-shell transition-metal complexe

Open-shell transition-metal complexe molecules

Open-shell wavefunction

Organic molecules closed/open shell

Other open-shell situations. Ensemble averaging

Quantum chemistry, open-shell molecules

ROHF (Restricted Open Shell Hartree

ROHF (Restricted Open Shell Hartree Saddle point

ROHF approximation open-shell

Random-phase approximation , open-shell

Reference functions, open-shell molecules

Restricted HF theory. An open-shell system

Restricted Open-Shell Kohn-Sham Theory (ROKS)

Restricted Open-shell Calculations

Restricted Open-shell Hartree-Fock ROHF)

Restricted Open-shell Hartree-Fock method

Restricted open shell Hartree-Fock Self-consistent

Restricted open shell Hartree-Fock field

Restricted open-shell

Restricted open-shell HF

Restricted open-shell Hartree-Fock

Restricted open-shell Hartree-Fock approximation

Restricted open-shell Hartree-Fock electron correlation methods

Restricted open-shell Hartree-Fock procedure

Restricted open-shell Hartree-Fock spin contamination

Restricted open-shell Kohn-Sham

Restricted open-shell Kohn-Sham ROKS)

Restricted open-shell formalism

Restricted open-shell reference functions

Semi-Cluster Expansion Theories for the Open-Shell States

Semiempirical method for transition metal complexes with open (-shells

Shell closed versus open

Slater determinants, open-shell molecules

Spin adaptation open-shell molecules

Spin contamination open-shell molecules

Spin multiplicity, open-shell molecules

Spin-restricted open-shell Hartree-Fock

Spin-restricted open-shell Hartree-Fock ROHF)

Spin-restricted open-shell Hartree-Fock ROHF) orbitals

Spin-restricted open-shell Hartree-Fock ROHF) reference functions

Spin-restricted open-shell Kohn-Sham

Spin-restricted open-shell Kohn-Sham method

Steric Effects of Open d Shells

Steric activity of the open d shell

Symmetry breaking open-shell molecules

Theoretical Model Chemistry and Its Relevance to the Open-Shell Formalisms

Transition open shell

Triplet open-shell ground states

Two open-shell system

Unrestricted Hartree-Fock restricted high-spin open-shell

Unrestricted and Restricted Open-shell Hartree-Fock Methods for Crystals

Unrestricted open-shell

Wave operator open-shell

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